Because of its magnetic properties, low cost and ample reserves, Nd—Fe—B composite magnets are widely used in vehicles, computers, electronics, mechanical and medical devices, to name a few. In addition, because of its performance to price ratio, Nd—Fe—B materials have been favored to produce magnetic devices with high efficiency, small volume and light mass. However, Nd—Fe—B materials are also known to have poor coercivity and mechanical properties, thereby limiting its applications to some extent.
The polymer-bonding method is usually used for preparing a permanent magnetic material. It is easy to press and form a blank, but the polymer and other additives have different structures compared with Nd—Fe—B magnets, which lead to poor mechanical properties of the Nd—Fe—B composite magnets.